Microwave ovens for preparing food are well known in prior art. Sophisticated models comprise a blower or fan in order to obtain air turbulences within the interior of the microwave oven.
Document DE 41 05 300 A1 discloses a blower for a microwave oven. The blower comprises a motor with a rotatable shaft extending through an opening of the oven muffle into the interior of the oven. At the free end of the rotatable shaft a blower wheel is attached. In order to reduce the microwave leakage through the opening, the opening matched to the rotatable shaft, the blower wheel, the dish connected with the oven muffle and a carrying plate of the motor form a microwave-proof blocking filter unit.
A drawback of the known microwave blocking filter unit is that due to the connection of the carrying plate with the oven muffle the suppression capability of the microwave blocking filter unit is decreased. Additionally, the microwave blocking filter unit comprises a complex structure and is therefore cost-intensive in manufacturing.